Overview

Virginia’s Sea Level Is Rising

And It’s Costing Over $4 Billion

The sea level around Hampton Roads is up to 14 inches higher than it was in 1950.1 This increase is mostly due to Virginia’s sinking land, and it’s causing major issues. Hampton roads is second only to New Orleans as the largest population center at risk from sea level rise in the country.2 These assets include important military bases, like Naval Station Norfolk. There are already over 45,000 properties at risk from tidal flooding in Virginia.3 The state is planning over $4 billion in sea level rise solutions, which include stormwater and sewage system protection projects.

Sea level rise is speeding up

The sea level around Sewells Point, Virginia, has risen by 14 inches since 1950. Its speed of rise has accelerated over the last ten years and it’s now rising by one inch every 4 years.1 Scientists know this because the sea level is measured every 6 minutes using equipment like satellites, floating buoys off the coast, and tidal gauges to accurately measure the local sea level as it accelerates and changes.4

Created with Highcharts 6.1.3Sea Level Change in Inches195019601970198019902000201020160246810121416

SEA LEVEL MEASUREMENT FROM SEWELL’S POINT AREA TIDE GAUGE SINCE 1950

Causes & Complications

Why Are Sea Levels Rising?

While there are four causes of sea level rise in Virginia, land sinkage is the main contributor.5 Because the land is getting about 1 inch lower every 10 years,6 Virginia is particularly vulnerable to an increased rate of sea level rise in the future. Click here to learn more about these causes.

How Land Sinkage Increases Sea Level Rise

Most flooding happens during the fall

King tides are unusually high tides that are created during months when the sun, moon, and earth align. The combined gravitational pull of the moon and the sun creates much higher tides, called king tides. In some places, king tides are brought on by changes in the weather and ocean patterns. In places like Sewells Point, king tides are typically nearly a foot and a half higher than normal.1 Add that to the 14 inches of sea level rise since 1950, and you end up with flooding even on sunny days.

Solutions aren’t simple

Hampton Roads is experiencing the highest rates of sea level rise along the entire East Coast.2 Solutions here and in other parts of Virginia can be complicated because the land is sinking from the shifting of land and also from the pumping of large volumes of groundwater from deep in the earth.7 To prevent continued land sinkage, the state will have to fill the underground voids that have been created.

We may not be able to prevent sea level rise or flooding, whether it is coastal or riparian, but we can do better to live with it and to prepare for it.

Susan Gaston, President and Owner of the Gaston Group

Forecast

What's the Future of Sea Level Rise?

In the last decade, the speed at which Virginia’s sea level is rising has increased, and is now rising by as much as 1 inch every 4 years.1 Around Hampton Roads, it took around 26 years for the sea level to rise 6 inches.1 Scientists now forecast that in just the next 13 years, the sea level will have risen by another 6 inches.8

Scientists are not certain how fast the ocean will warm and ice will melt. They expect water levels to continue to rise faster, but are not sure just how fast. Therefore scientists from the National Oceanic and Atmospheric Administration (NOAA) and the US Army Corps of Engineers (USACE) have made predictions based on ranges from low to high.

Below you can see the range of the NOAA and USACE high and intermediate forecasts for various locations around Virginia.9 Currently, the USACE high forecast, seen as the darkest red line, is the most likely projection.

SLR speeding up - Virginia English
SLR speeding up - Virginia English
Sewells Point
Created with Highcharts 6.1.3YearInchesSewells Point Sea Level Rise Forecasts201620262036204620500510152025

For particular communities and population groups, the cumulative economic loss and erosion in health stemming from recurrent flooding [from sea level rise] may actually surpass the impact of a single catastrophic event.

Joshua Behr, Research Associate Professor at Old Dominion University

Flooding

Why Are Floods More Frequent?

When the ocean rises high enough, high tides cause flooding even on sunny days. Even though the sea level has only risen by around 5 inches, tidal flooding has increased by 132% in some areas of Virginia since 2000.10

Flooding
How sea level rise effects Virginia

Flooding even when there’s no rain

Drainage systems are designed to channel excess rainwater from the streets and drain it into the sea. But with the pressure from rising sea levels and higher tides, seawater can get pushed into these pipes and spill out into the streets. This causes flooding even on days without rain.

Drain A
Drainage Under Normal Tidal Conditions
Drainage With High Tide / Sea Level Rise

Increased storm surge flooding

Unfortunately, slightly higher sea levels make hurricanes even more damaging. Just a few more inches of sea level rise allow a hurricane to push more water onto the land, even if the hurricane itself doesn’t make landfall.

Hurricane Irene, 2011

Higher sea levels create a higher launching point for storm surge. These small changes in sea level rise are enough to turn what were 100-year storm surges into much more frequent events. In fact, in a third of 55 coastal sites studied throughout the US, 100-year storm surges will be 10-year or more frequent events by 2050.11

This means that in many coastal cities, if you bought a house with a 30-year mortgage today, by the time you paid off your mortgage you could be experiencing extreme 100-year storm surges ten times more frequently due to sea level rise alone. This does not include the added risk of more intense storms resulting from warmer water and a warmer atmosphere, which could further increase storm surge damage.

In 2011, Hurricane Irene made landfall as a Category 2 hurricane and caused $269 million in damages to the state.12 Without sea level rise, Hurricane Irene’s 4.4 foot storm surge would have been lower.13

Hurricane Irene, 2011

Costs

What's at Risk in Virginia?

There’s a lot at risk from sea level rise and flooding in Virginia, especially because the state is home to important military infrastructure. The Norfolk-Virginia Beach Metropolitan Area ranks 10th in the world in value of assets exposed to an increase in flooding from sea-level rise.2 These assets include places like Naval Station Norfolk, which would need to spend up to $460 million to replace old piers already degraded by sea level rise and hundreds of millions more to protect onshore infrastructure critical to the base’s maintenance, training, and logistics missions.2 In addition, there are many residential properties and other types of infrastructure at risk.

Military Infrastructure
Military Infrastructure

Rising seas can erode the beaches of important military infrastructure and damage or shut down military ports. Flooding can make it impossible for service-people to reach or leave bases.

Schools and Hospitals
Schools and Hospitals

Flooding can also impact critical community resources such as neighborhood schools and hospitals.

Homes & Cars
Homes & Cars

Storm surges or flooding can damage the underside of your car or the first level of your home.

In Chesapeake there are 4,507 residential properties already at risk from repeated tidal flooding, by 2033 that number will increase to 5,562 as sea levels rise. In Norfolk, 4,132 properties at risk will turn into 5,624 within 15 years. In Virginia Beach there are 6,208 properties at risk, which will become 8,096. And in Portsmouth, there are 1,427 properties at risk, which will increase to 1,840 by 2033. Click here to explore other coastal areas in Virginia that are at risk at FloodiQ.com.

Virginia is spending over $4 billion

Some cities have sufficient resources to deal with this problem while others do not. Virginia will need solutions at the individual, local, state, and federal levels to protect its coastal communities.

Norfolk
Norfolk

Norfolk has over $1 billion of proposed projects to protect against flooding by 2035.14

Virginia Beach
Virginia Beach

Virginia Beach has allocated $450 million for stormwater projects in the next 5 years.15

Hampton Roads
Hampton Roads

Hampton Roads has allocated $240 million toward projects to protect sewage systems from flooding.16

What can you do?

Individuals, mayors, legislators, governors, and Congress can work together to build protections before flooding, to build back stronger after flooding, and to create plans that future-proof our communities. Click here to see what solutions can help protect your home or what your community can do.